ass日本风韵熟妇pics男人扒开女人屁屁桶到爽|扒开胸露出奶头亲吻视频|邻居少妇的诱惑|人人妻在线播放|日日摸夜夜摸狠狠摸婷婷|制服 丝袜 人妻|激情熟妇中文字幕|看黄色欧美特一级|日本av人妻系列|高潮对白av,丰满岳妇乱熟妇之荡,日本丰满熟妇乱又伦,日韩欧美一区二区三区在线

When the traditional single motor driven electric tractors were plowing and rotary tillage, the driving motor was often in the low efficiency area. The power of the motor cannot be fully utilized, which leads to the reduction of working time of tractor. Compared with the single-motor driving system, the dual-motor driving system has some advantages, including the operating point of the two motors can be adjusted to optimize the efficiency of the driving system. It can reduce the torque capacity of the single motor, improve the power density of the driving system, and increase the energy efficiency of the tractor under different operating conditions. Firstly, the structure and working principle of the dual-motor coupling driving system for electric tractors were proposed, including single-motor mode and dual-motor mode. According to the proposed structure, combined with the transmission characteristics of the planetary gear mechanism, the driving mode of the dual motors coupled driving system was analyzed and calculated. Secondly, the mathematical model of powertrain for electric tractor was established. On this basis, the simulation test model for electric tractor was built. The coordinated control strategy of the dual motors driving system was designed, and the power distribution rules of the two motors were obtained by simulation test, the simulation results showed that the power distribution ratio of two motors was between 1.31 and 2.62. Finally, a transmission test platform was built and tested under constant load and traction performance was done. The result demonstrated that under the two load conditions, the power distribution ratio of two motors was ranged from 1.07 to 2.73. In constant load test, the system efficiency was the highest when the power distribution ratio was 1.88. When the power distribution ratio was 1.85, the system efficiency was the highest in traction performance test. The dual motors driving system could realize the power distribution of the two motors according to the power distribution rules, which met the working load and reduced the power loss at the same time. Therefore, selecting the corresponding driving modes according to the different working conditions can improve the efficiency of the driving system.